Many people contend with spine issues as a result of age, disease, and trauma, as well as congenital and acquired complications and conditions. While some of these issues can be alleviated without surgery, other issues necessitate surgery. Spinal fusion may be recommended for conditions such as spondylolistheses, degenerative disc disease, or recurrent disc herniation, and is designed to create solid bone between adjacent vertebrae, thereby eliminating any movement between the bones. A spinal fusion uses an implant or device known as an interbody cage or spacer along with bone graft and/or bone graft substitute that is inserted into the disc space between adjacent vertebrae from one side of the spine. Typically, additional surgical hardware (implants) such as pedicle screws and rods or plates are attached to the back of the vertebrae. As the bone graft heals, it fuses the adjacent vertebrae to form one long vertebra.
A fusion of the lumbar region of the spine (a lumbar fusion) may be accomplished using several techniques. Once such technique is known as an anterior lumbar interbody fusion or ALIF. ALIF spine surgery is performed through the anterior aspect of the spine and provides stabilization of the spine. In an ALIF, the disc space is fused by approaching the spine through the abdomen. In one approach, an incision is made on the left side of the abdomen and the abdominal muscles are retracted to the side. Since the anterior abdominal muscle in the midline (the rectus abdominis) runs vertically, it does not need to be cut and easily retracts to the side. The abdominal contents lay inside a large sack (peritoneum) that can also be retracted, thus allowing the spine surgeon access to the front of the spine without actually entering the abdomen.
After the blood vessels have been moved aside, the disc material is removed and bone graft typically with an anterior interbody cage is inserted. The ALIF approach is advantageous in that both the back muscles and nerves remain undisturbed. Another advantage is that placing the bone graft in the front of the spine places it in compression, and bone compression tends to fuse better. Moreover, a much larger implant can be inserted through an anterior approach, providing for better initial stability of the fusion construct. When an interbody cage is used, it is important that it is securely anchored.
However, there is room for improvement over current ALIF implants, instruments, and/or surgical procedures.
In view of the above, it is an object of the present invention to provide an improved ALIF implant, an instrument for implanting the improved ALIF, and/or a surgical procedure for the implantation.